First-principles calculations to investigate structural, electronics, mechanical, and optical properties of KGaO3 cubic perovskite for photocatalytic water-splitting application

A first-principles investigation has been used to construct the crystal structure with space group 221 that has cubic nature developed in CASTEP software. A pseudo-potential plane-wave technique inside the GGA (generalized-gradient-approximation) and PBE (Perdew-Burke-Ernzerhof) exchange-correlation functional are used to investigate the KGaO3 compound. The present research report is on the structural, electronics, mechanical, and optical properties of KGaO3. The electronic properties reveal that the material is semi-conductor and has indirect band gap of 2.74 eV which reduce the electron-holes recombination. The elastic constant values were also investigated and utilized to investigate mechanical parameters such as shear modulus, Young's modulus, and Poisson's ratio. According to elastic constants calculations, KGaO3 are mechanically stable and ductile in nature. Further, refractive index, optical conductivity, the dielectric-constant, reflectivity, absorption coefficient, extinction coefficient, and loss function are calculated. According to the results, KGaO3 exhibits a high absorption in the visible region. This limits its application in photocatalytic water splitting characteristics.